Batteries have existed for many years. Recently lithium oxygen or lithium air batteries have been researched as a power supply. These lithium batteries have utilized a polymer based electrolyte positioned between the cathode and anode. Batteries using these polymer electrolytes however quickly degrade when exposed to ambient air due to the fact that they 1) do not provide adequate moisture barrier protection for the lithium anode and thus the lithium anode reacts with moisture and quickly degrades and 2) they employ electrolyte in the cathode that is volatile and very unstable in ambient air resulting cathode dry out and or reactions with ambient air gasses resulting in degraded performance.
These batteries typically utilize an aluminum cathode current collector. However, the use of aluminum as the current collector requires an electrolyte that can passivate the aluminum surface to reduce corrosion. Typically, these batteries utilize an electrolyte salt such as lithium hexafluorophosphate (LiPF6) to passivate the aluminum. However, LiPF6 should not be utilized in an environment in which oxygen or water is present, thus making it unacceptable for use with Lithium oxygen or air batteries, as it is known to hydrolyze for form HF, which attacks any metal oxides commonly used as oxygen redox catalysts. It is also believed that the PF6 breaks down in this environment which likely contributes to the capacity fade of the battery.
An additional problem with aluminum current collectors stems from the fact that they make up a significant portion of the weight in an air cathode of a lithium air or lithium oxygen battery. This results in a lower overall specific energy density for the battery cell.
It thus is seen that a need remains for an electrolyte for a lithium air battery which overcomes problems associated with those of the prior art. Accordingly, it is to the provision of such that the present invention is primarily directed.